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arXiv · 1907.00608

Tri-partite non-maximally entangled mixed states as a resource for optimum controlled quantum teleportation fidelity

K. G. Paulson·Prasanta K. Panigrahi
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Abstract

Three-qubit mixed states are used as a channel for controlled quantum teleportation (CQT) of single-qubit states. The connection between different channel parameters to achieve maximum controlled teleportation fidelity is investigated. We show that for a given multipartite entanglement and mixedness, a class of non-maximally entangled mixed $X$ states ($X-$NMEMS) achieves optimum controlled quantum teleportation fidelity, interestingly a class of maximally entangled mixed $X$ states ($X-$MEMS) fails to do so. This demonstrates, for a given spectrum and mixedness, that $X-$MEMS are not sufficient to attain optimum controlled quantum teleportation fidelity, which is in contradiction with the traditional quantum teleportation of single qubits. In addition, we show that biseparable $X-$NMEMS, for a certain range of mixedness, are useful as a resource to attain high controlled quantum teleportation fidelity, which essentially lowers the requirements of quantum channels for CQT.

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K. G. Paulson, Prasanta K. Panigrahi. 2019-11-19. Tri-partite non-maximally entangled mixed states as a resource for optimum controlled quantum teleportation fidelity. https://doi.org/10.1103/physreva.100.052325

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